Charles d



(No Model.)

y C. D. TISDALB.

AUTOMATIC ELECTRIC FIRE ALARM.

No. 546,261. .Patented Sept. 10, 1895.

ANDREW EJSRANAM. PNUTOMTHQWASNINGTUN ILC y UNITED STATES;

PATENT OFFICE.

CHARLES D. TISDALE, OF BOSTON, MASSACHUSETTS, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, OF TWO-THIRDS TO JOHN D. GOULD, OF BROOK- LYN, AND CHARLES A. HANSON, OF NEW YORK, N. Y.

AUTOMATIC ELECTRIC FIRE-ALARM.

SPECIFICATION forming part of Letters Patent No. 546,261, dated September 10, 185.

Application filed February 12, 1895. Serial No. 538,121. (No model.)

To a/ZZ whom it may concern:

Be it known that I, CHARLES D. TIsDALE, of Boston, in the county of- Suolk and State of Massachusetts, have invented certain new and useful Improvements in Automatic Electric Fire-Alarms, of which the following is a full, clear, and exact description.

The object of the present invention is to provide a simple, cheap, and efficient electriio cal thermostat or electrical fire-alarm system for use more particularlyin apartment houses, dwellings, buildings, duc., although applicable as well to stores, warehouses, factories, the.; and the invention consists, in combinar 5 tion with a room or other apartment or place,

of a tube of any suitable material and construction located in the room or other place, of mercury or other suitable heat-expanding liquid material within the tube, an electric zo circuit, and a sounding device, all constructed and arranged for operation, substantially as hereinafter fully described, reference being had to the accompanying sheet of drawings, in which is illustrated the present invention. 2 5 Figure l is a detail perspective View of two walls of a room with this invention applied thereto; Fig. 2, a longitudinal section of the tube and connecting parts. Fig. 3 is a dia# gram of the electric circuit. 3o In the drawings, A B represent in detail two sides of a room in a house, and C the mopboard.

As shown in the drawings, on one side of the room along the mop-board is a tube D, preferably of metal and of small diameter, and at one end it is bent upward and its end E secured in the bottom of a vertical tube F, preferably of larger diameter. Within this vertical tube Fis a glass tube G, and secured therein by cement a, and adapted to screw onto the upper end of the vertical tube is a cap H, the central portion of which is filled with an insulating material J', which extends through a central opening b in the head'of the cap. Over the other end of the tube D is secured by a screw-thread the end of another metal tube K, preferably of larger diameter, and on this tube K is screwed another tube or long cap L. 5o Within the chamber d of the tube K is a plunger or piston M, adapted tol move back and forth therein,having a central rod e, extending along the cap-tube L, and projecting out through a central openingf in its end, and on the end of this rod are two flanges g h, one g of which is inside the tube and bears against the inside of the cap end and the other h bears against the outside, holding the rod e to the cap L, but allowing free turning of the cap thereon. The tube-cap L is ar- 6o ranged to screw back and forth on the tube K, and in its movements it carries with it the piston M along the tubechamber d.

P is avertical tube or spout having a daring mouth m, to be closed by a stopper n. Mercury N is poured into the spout, which flows into the chamber d, between the plunger M and tube D, along the chamber of the tube D and up the glass tube-chamber, the plunger being moved in or out to adjust the height 7o of the mercury in the glass tube to the temperature of the room at the time. A longitudinal slitt is made in the front of the metal tube F over the glass tube G, so the glass tube and the mercury therein at such place can be seen, and along this slit is a scale u of degreesfor instance, Fahrenheitand it is preferably arranged for the mercury in the glass to indicate in the usual manner of thermometers the degrees of heat in the room, although any 8o suitable scale can be used. Extending down through the insulating material J into the glass-tube chamber is a metal wire Q which is f-l arranged to be moved up and down therein, as desired. This wire Q and the mercury in the tube are connected electrically with an electric battery, as follows: From the wire Q extends an electric wire R to an armature S, pivoted at 'u to a support, and from this eX- tends a wire T which connects with an electro- 9o magnet U. From the electromagnet runs another wire V to a mechanism for a bell YV, and from this mechanism runs another wire Y to one pole of an electric battery A.

From the pole of the electric battery extends a wire B which connects with the cap H of the vertical tube F, or it can connect with the tube D at any place, so it can make an electric connection With the mercury therein.

Connected to the wire B is a wire C con- Ico nected to a metal plate D', havinga point w, which, as shown, is a little distance below the electromagnet, its point w projecting beyond the vertical plane ofthe end a' of the magnet, so that it the armature S is drawn toward the magnet, it being of suitable length, it will bear upon the plate D', but not touch the magnet, as shown in dotted lines in Fig. 3. lVith a room having this system of electrical lirealarm located therein, and connected to any suitable sounding device at any place desired, the wire Q is moved up in the glass tube until its lower end h is at the degree of the scale representing the heat at which the alarm is to be given, which might be one hundred and titty or two hundred or other degrees. New if the fire occurs in any part of the room the tube at such place becomes heated,which communioates heat to the mercury therein, causing it to expand suihciently for it to rise in the glass tube until it touches the end of the wire Q. Instantly from the contact ofthe two, electric circuit is made, causing the bell to sound, giving warning of the lire in the room where this device is placed. At the same time the electromagnet attracts the armature S until it bears and rests upon the plate D', which, as soon as it does, short-circuits the electric current by making the circuit from the plate through the battery-bell, magnet, and armature, which circuit will then be maintained, continuously sounding the bell. The object of this short circuit is to keep thebell sounding as long as possible to insure warning being given to the person desired-as, for instance, without this arrangement of short circuit, if from one cause or another the mercury, after it had made contact and the electric circuit, as described, should drop from its contact with the wire, thus breaking the electric circuit, the sounding ot the bell or alarm would cease, which would often fail to accomplish the result desired, for it the person who it was intended should be notilied of the tire should at that particular time be away he would not hear the alarm; but with the continuous sounding' of the bell by the maintaining of the circuit through the plate the person would be sure to be notified sooner or later.

lhe tube D can be very small in diameter, in order not to use much mercury and to take up little room. As shown, it is only on one side of the room. It can extend away around the room along the mop-board or at any desired place and height in the room--for instance, when near the floor can be disposed in one of the hollows or grooves of the holding of the mop-board-and can be ornamented, as desired. The vertical tube and glass tube can be arran ged in any part of the roo m desired, also the battery can be in any suitable place in or out of the room. The bell, however, is preferably arranged to be in some other room or outside the room or corridor, or on the outside et' the building, or in any other building cr room.

The great advantage et' this system et electrical tire-alarm is that the tube with the mer cury can extend around the room indefinitely and into all places connected therewith, maliing what might be called a continuous tubular electric thermostat, so that the instant flame or extreme and dangerous heat touches or warms up any part of the continuous tube the mercury therein immediately expands, which forces up its column in the glass tube into contact with the terminal or electrode wire Q, making the electric circuit and giving the alarm, which by the means or" the electromagnet and the short-circuiting et the electric current continues to sound until some party is notified. By this arrai'igement of the tube so extensively around the room or other place an alarm will be given immediately at the start of the fire and before it becomes'dangerous or of any magnitude, which, as is obvious, is very important. The means for adjusting the height of the mercury in the tube-that is, by the chamber at one end with the piston therein and means for operating it is advantageous for electrical thermostats for any purpose, as by it the mercury can be easily and conveniently raised or lowered in the scale portion of the tube, as desired, and for such purpose other ways can be used in lieu of the piston. i

Having thus described my invention, what I claim is l. In an electric tire alarm device, a tube extended along and around the side or sides ot a room or other place, an upward extension of said tube, a wire connected with one pole of an electric battery arranged in said tube extension insulated therefrom, a chamber at the other end of said iirst tube, a plunger er piston therein, and operated from the outside, and mercury in said tubes and chamber and connected electrically with the other pole of the electric battery.

2. In an electric lire alarm device, a tube arranged along and around the side or sides of a room or other place, an upward extension of said tube, a glass tube within said exten sion, a cap screwing onto said tube extension having insulating material therein, a wire extending through the insulating material and into the glass tube connected with one pole of an electric battery, and mercury in said first tube and glass tube connected electrically with the other pole of the electric bat tery.

3. In an electric fire alarm device, a tube arranged along and around the side or sides of a room or other place, an upward extension of said tube, a wire connected with one pole ot an electric battery, arranged in said tube extension insulated therefrom, mercury in said tube, connected electrically with the ICO IXO

other pole of the electric battery, e tube of In testimony whereof I have hereunto set larger diameter secured to the other end of my hand-in the presence of two subscribing Io vsaid rst tube, e chamber therein, a cap Witnesses.

screwing onto the end of said latter tube, a

plunger or piston in said chamber, aI rod eX- CHARLES D' TISDALE tending from said plunger out through the Witnesses:

heed of said cap and connected thereto by EDWIN W. BROWN,

flanges on said rod. LEONA C. ARNO. 

